I'm still too new to be unmotivated perhaps, but I think I know what you mean...
Right now, I'm about to squeeze ten miles in because it will be dark soon but the rain has abated. Yet the winds will be a force, no doubt. I'll do the ride because I know how I'll feel when I'm done. And because I can log it on BikeJournal.com. And because at the end of the day I know I'll have done at least one little thing that's good for me.
Tomorrow's a holiday in the U.S. and there's a million work-related things I should/could do. Maybe I'll seize that opportunity, or maybe I'll just take the bike over to Coronado and see if I can get in a half century.
My biggest problem is how early it gets dark. I'm NOT, NOT, NOT a morning person. I'm so not a morning person. Not only that, I don't like mornings.
I guess I'm not helping much. Better go ride.